Originally Posted by PatriceJ

yes ... added the corner triangles to the windmill row before joining it to the two big triangle-shaped units.
i am not 100% sure it must be done that way. i'd have to make a third copy of the block to find out - which i don't plan to do at this time.

did you starch your fabrics before you cut out your pieces? i always starch the heck out of my fabrics before i make the first cut. if i'm going to be working with any angles at all, i starch the double-heck out of it. the stiffer the fabrics the easier it is [for me] to cut accurately; match the pieces; and sew accurate seams without stretching things out of shape.

i also used a lot of pins when it came time to join each of the large triangular units to the windmill row.
i started by pinning each of the points where the triangles poked up against the corners of the square.

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after making sure my "point pins" were as straight as possible i added pins on each side.

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then i stitched between those pins and checked to see if they'd joined up properly. when they don't, i only have to remove a few stitches instead a whole seam. once i have them joined well enough, i sew the whole seam.

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